#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
MODULE_AUTHOR("XIAOSHOU");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("xiaoshou_IRQ driver test!");
//#define DEG //调试
#ifdef DEG
#define DEBUG(msg,arg...) printk("kernel_debug message:#>: "msg,##arg)
#else
#define DEBUG(msg,arg...)
#endif
#define IO_DEL 0
#define CMD1 1
#define CMD2 2
#define DEV_COUNT 1
#define DEV_NAME "IRQ_XSH"
#define MAX_BUF_LEN 16
#define SIZE MAX_BUF_LEN
#define INCBUF(x) (++(x)%(MAX_BUF_LEN))
#define DECBUF(x) (--(x)%(MAX_BUF_LEN))
struct device_xsh
{
unsigned int flag;
unsigned char buf[MAX_BUF_LEN];
unsigned int head,tail;
wait_queue_head_t wq;
struct cdev irq_cdev;
};
static int minor_num = 0;
static int major_num = 0;
static struct device_xsh irq_device;
static struct class *irq_class;
ssize_t irq_read(struct file *filp,char __user *buf,size_t count,loff_t *f_ops);
ssize_t irq_write(struct file *filp,const char __user *buf,size_t count,loff_t *f_ops);
int irq_open(struct inode *inode,struct file *filp);
int irq_release(struct inode *inode,struct file *filp);
int irq_ioctl(struct inode *inode,struct file *filp,unsigned int cmd,unsigned long arg);
static irqreturn_t buttons_irq_isr(int irq,void *dev_id,struct pt_regs *req); //中断服务程序
static void do_task_irq(void); //任务队列的执行函数；
DECLARE_TASKLET(task_irq, do_task_irq, 0); //中断服务下半部分的任务队列；
struct file_operations irq_fops =
{
.owner = THIS_MODULE,
.read=irq_read,
.write=irq_write,
.open=irq_open,
.release=irq_release,
.ioctl=irq_ioctl,
};
static int __init irq_init(void)
{
dev_t dev_num=0;
int res;
int err;
unsigned long bitval ;
//###########分配设备号-start####################
if(major_num) //手动分配设备号
{
dev_num=MKDEV(major_num,minor_num);
res=register_chrdev_region(dev_num,DEV_COUNT,DEV_NAME);
}
else //动态分配设备号
{
res=alloc_chrdev_region(&dev_num,minor_num,DEV_COUNT,DEV_NAME);
major_num=MAJOR(dev_num);
}
if(res<0)
{
DEBUG( "IRQ alloc_chrdev_region error!!\n");
return -1;
}
//#########//申请中断//########################
set_irq_type(IRQ_EINT3,IRQT_FALLING); //下降沿触发；
res =request_irq(IRQ_EINT3,&buttons_irq_isr,SA_INTERRUPT,DEV_NAME,NULL);
if(res<0)
{
DEBUG( "request_irq error_num= %d!!\n",res);
return -1;
}
//###########分配设备号-end####################
//############设备初始化#######################
memset(&irq_device,0,sizeof(struct device));
memset(irq_device.buf,0,sizeof(unsigned char)*SIZE);
irq_device.flag=0;
init_waitqueue_head(&(irq_device.wq)); //初始化队列；
//############注册设备-start#######################
cdev_init(&(irq_device.irq_cdev),&irq_fops);//cdev 结构嵌入一个自己的结构体需初始化
irq_device.irq_cdev.owner=THIS_MODULE;
irq_device.irq_cdev.ops=&irq_fops;
err=cdev_add(&(irq_device.irq_cdev),dev_num,1);
if(err!=0)
{
DEBUG("IRQ cdev_add error!!\n");
}
irq_class=class_create(THIS_MODULE, "irq_class"); //udev自动创建/dev/设备文件
class_device_create(irq_class, NULL, dev_num, NULL, DEV_NAME);
DEBUG("insmod char_irq success!\n");
return 0;
}
static void __exit irq_exit(void)
{
dev_t dev_num;
dev_num=MKDEV(major_num,minor_num);
cdev_del(&(irq_device.irq_cdev));
class_device_destroy(irq_class, dev_num);
class_destroy(irq_class);
free_irq(IRQ_EINT3,NULL);
unregister_chrdev_region(dev_num,1);
DEBUG("rmmod char_irq success!\n");
return ;
}
int irq_open(struct inode *inode,struct file *filp)
{
struct device *my_device;
try_module_get(THIS_MODULE); //表示此驱动被使用，记数器增加
my_device=container_of(inode->i_cdev,struct device_xsh,irq_cdev);
filp->private_data=my_device;
DEBUG("IRQ_char open success!!\n");
return 0;
}
int irq_release(struct inode *inode,struct file *filp)
{
DEBUG("IRQ_char release success!!\n");
module_put(THIS_MODULE); //表示此驱动使用完毕，记数器减一
//free_irq(IRQ_EINT3,NULL);
return 0;
}
ssize_t irq_read(struct file *filp,char __user *buf,size_t count,loff_t *f_ops)
{
int err;
char tmp;
retry:
if(irq_device.head!=irq_device.tail)
{
tmp=irq_device.buf[irq_device.tail];
err=copy_to_user(buf,&tmp,1);
DEBUG("irq_device.buf=0x%x\n",irq_device.buf[irq_device.tail]);
if(err!=0)
{
DEBUG("irq_char copy_to_user error!!\n");
return 0;
}
irq_device.tail=INCBUF(irq_device.tail);
return 1;
}else
{
if(filp->f_flags & O_NONBLOCK)
{
return -EAGAIN;
}
wait_event_interruptible(irq_device.wq,irq_device.flag);
irq_device.flag=0;
if(signal_pending(current))
{
printk("rturn -ERESTARTSYS\n");
return -ERESTARTSYS;
}
goto retry;
}
return 1;
}
ssize_t irq_write(struct file *filp,const char __user *buf,size_t count,loff_t *f_ops)
{
int err;
memset(irq_device.buf,0,sizeof(char)*SIZE);
err=copy_from_user(irq_device.buf,buf,count);
if (err!=0)
{
DEBUG("irq_char copy_from_user error!!\n");
return 0;
}
return count;
}
int irq_ioctl(struct inode *inode,struct file *filp,unsigned int cmd,unsigned long arg)
{
switch(cmd)
{
case IO_DEL:
DEBUG( "ioctl IO_DEL success!");
break;
case CMD1:
DEBUG( "kernel_debug : IO CMD1=%d\n",CMD1);
break;
case CMD2:
DEBUG( "kernel_debug : IO CMD2=%d\n",CMD2);
break;
default:
return;
}
}
static irqreturn_t buttons_irq_isr(int irq,void *dev_id,struct pt_regs *req)
{
DEBUG( "IRQ_ISR \n");
tasklet_schedule(&task_irq); //任务调度中断下半部分服务程序；
return IRQ_HANDLED; //返回中断已经获得；
}
static void do_task_irq(void)
{
irq_device.buf[irq_device.head]='K';
DEBUG("irq_device.head=%d\n",irq_device.head);
DEBUG("irq_device.buf=0x%x\n",irq_device.buf[irq_device.head]);
irq_device.head=INCBUF(irq_device.head);
irq_device.flag=1;
wake_up_interruptible(&(irq_device.wq));
//DEBUG( "do_task_irq \n");
}
module_init(irq_init);
module_exit(irq_exit);
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